Oil Linear Density model¶
The linear density model requires the input of a reference density, pressure and temperature, and compressibility and expansion coefficients. See example below:
EOS OIL
DENSITY LINEAR
REFERENCE_VALUE 833.5d0 !den0 [kg/m3]
PRES_REF_VAULE 5.516d6 ![Pa]
TEMP_REF_VALUE 94.8 ![°C]
COMPRESS_COEFF 1.672d-7 !C [kg/m3/Pa]
THERMAL_EXPANSION_COEFF 0.0d0 !E [kg/m3/°C]
END
ENTHALPY LINEAR_TEMP 1.d3 !c oil [J/kg/°C]
VISCOSITY CONSTANT 0.987d-3
END
The mathematical expression of the model is reported below:
\[\rho= \rho_0 + C ( p − p_0 ) − E ( T − T_0 )\]
where:
\[\begin{split}\begin{split}
& p &= \mbox{pressure [Pa]} \\
&T &= \mbox{temperature [°C]} \\
&\rho_0 &= \mbox{reference density [kg/m3]} \\
&p_0 &= \mbox{reference pressure [Pa]} \\
&T_0 &=\mbox{reference temperatures [°C]} \\
&C &=\mbox{compressibility coefficient [kg/m3/Pa]} \\
&E &=\mbox{thermal expansion coefficient [kg/m3/°C]}
\end{split}\end{split}\]
Units cannot be specified, therefore values must be entered in the units prescribed above.